drm/exynos: use a new anon file for exynos gem mmaper
This patch resolves potential deadlock issue that can be incurred
by changing file->f_op and filp->private_data to exynos specific
mapper ops and gem object temporarily.
To resolve this issue, this patch creates a new anon file dedicated
to exynos specific mmaper, and making it used instead of existing one.
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
index 7e074a4..9d096a0 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -14,6 +14,8 @@
#include <drm/drmP.h>
#include <drm/drm_crtc_helper.h>
+#include <linux/anon_inodes.h>
+
#include <drm/exynos_drm.h>
#include "exynos_drm_drv.h"
@@ -152,9 +154,14 @@
return 0;
}
+static const struct file_operations exynos_drm_gem_fops = {
+ .mmap = exynos_drm_gem_mmap_buffer,
+};
+
static int exynos_drm_open(struct drm_device *dev, struct drm_file *file)
{
struct drm_exynos_file_private *file_priv;
+ struct file *anon_filp;
int ret;
file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
@@ -169,6 +176,16 @@
file->driver_priv = NULL;
}
+ anon_filp = anon_inode_getfile("exynos_gem", &exynos_drm_gem_fops,
+ NULL, 0);
+ if (IS_ERR(anon_filp)) {
+ kfree(file_priv);
+ return PTR_ERR(anon_filp);
+ }
+
+ anon_filp->f_mode = FMODE_READ | FMODE_WRITE;
+ file_priv->anon_filp = anon_filp;
+
return ret;
}
@@ -181,6 +198,7 @@
static void exynos_drm_postclose(struct drm_device *dev, struct drm_file *file)
{
struct exynos_drm_private *private = dev->dev_private;
+ struct drm_exynos_file_private *file_priv;
struct drm_pending_vblank_event *v, *vt;
struct drm_pending_event *e, *et;
unsigned long flags;
@@ -206,6 +224,9 @@
}
spin_unlock_irqrestore(&dev->event_lock, flags);
+ file_priv = file->driver_priv;
+ if (file_priv->anon_filp)
+ fput(file_priv->anon_filp);
kfree(file->driver_priv);
file->driver_priv = NULL;